A line of lights embedded in the streets and pavements of central Rotterdam, tracing the exact boundary of the firestorm that destroyed the city centre after the German bombing of 14 May 1940. The lights run for several kilometres, and crossing the line means stepping from the area that survived into the area that was completely erased.
The memorial is subtle — you can walk over it without noticing — but once you understand what it marks, the modern architecture of Rotterdam's centre takes on a different meaning. Everything inside the boundary is post-war because everything that was there before was destroyed. The contrast with the older neighbourhoods just outside the line, like Delfshaven, is stark. Most visible at dusk and after dark when the lights glow in the pavement.